Title

Authors

Date of Completion

7-19-2019

Embargo Period

7-19-2019

Advisors

Jason Henderson, Karl Guillard, John Inguagiato, and Victoria Wallace

Field of Study

Plant Science

Degree

Master of Science

Open Access

Open Access

Abstract

The use of pesticides on home lawns and athletic fields is often a contentious issue due to concerns regarding human exposure and subsequent negative health impacts. Three studies are presented to; 1) evaluate different management regimes for home lawns and athletic fields, 2) assess overseeding strategies for non-irrigated, pesticide-free sports fields and 3) quantify the persistence of dislodgeable, foliar residue of four commonly used herbicidal active ingredients. Results of the home lawn and athletic field management studies indicate that treatments utilizing synthetic pesticides had significantly fewer weeds compared to organic and pesticide-free treatments. However, when averaged across years and season, percent weed cover did not exceed 33% for organic or pesticide-free treatments. Differences in weed cover did not result in significant desirable species cover retention or excessive surface hardness values. Species selection was the most important overseeding factor when overseeding non-irrigated, pesticide-free athletic fields. Perennial ryegrass had significantly higher color, quality, percent turfgrass cover and the lowest percent weed cover compared to tall fescue and Kentucky bluegrass. Finally, the dislodgeable, foliar residues decreased with increasing days after treatment. Granular formulations had significantly less residue in fewer days after treatment compared to sprayable formulations. The highest residues detected were from 2,4D, but equated to 0.6% of EPA’s No Observed Adverse Effects Level’ (NOAEL) risk assessment. All dislodgeable residues detected from pesticide applications sharply declined with precipitation in both years and were well below the EPA’s NOAEL risk assessment for physical activity on treated turfgrass for children 1 to 2-years-old.